Orbital ATK prepares for OA-6 Cygnus prior to Antares return

While the OA-4 Cygnus enjoys the berthed phase of her mission, Orbital ATK managers are already deep into parallel planning work with the Cygnus cargo resupply flight. The OA-6 Cygnus will also fly on the United Launch Alliance Atlas V, ahead of the company’s long-awaited transition back to its own upgraded Antares rocket.

“We have our pre-ship (review) with our service module the second week of January and right around January 25th we should arrive down here (Florida).”

After the Cygnus hardware arrives, Orbital ATK, ULA, and NASA workers will largely repeat the processing steps that the OA-4 spacecraft went through. The modules will once again be processed for flight in KSC’s Space Station Processing Facility (SSPF).

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The PCM will be loaded with most of the OA-6 flight’s cargo manifest before being joined with the service module. The mated spacecraft will then be rotated to vertical and transported to the Payload Hazardous Servicing Facility (PHSF) where the service module maneuvering propellant will be loaded.

Cygnus will then be rotated back to horizontal for late loading of remaining cargo into the PCM before being returned to vertical for encapsulation in the Atlas payload fairing.

The encapsulated spacecraft will then be transported from the PHSF out to the Vertical Integration Facility (VIF) at LC-41 for mating with the Atlas.

“We went through a PDR (Preliminary Design Review) in February and a CDR (Critical Design Review) in June and it’s been manufacturing and production since then.

“We received our first two flight engines in July and we already had the core (the first stage) and we modified it in place at Wallops to accommodate the new engines. There’s a new thrust frame and then new feedlines and those are really the major components that changed.

“(Also) those engines are now mounted to the thrust frame on the back of the core and there are feedlines connecting the two and so we’re going through checks.”

“Right now, we have Orbital ATK avionics controlling the engine valves and the thrust vector control actuators and so on,” Eberly added. “So it’s a lot of electrical checkout, there’s a ton of sensors that need to be verified – we’re kind of in an electrical and hydraulic testing phase right now.

Roll out to the pad is slated for mid-February and then stage test would be (around) the second week of March, but that’s subject to change.”

Once the first stage test article is out at the pad, a series of tests will be conducted prior to the hot-fire test.

“About 10 days before (the hot-fire), we going to run the automated sequence right up to ignition and stop right before ignition,” Eberly noted. “It’s a little bit different because it’s just the first stage.

“We’ll have an upper stack simulator and put the flight computer down in a vault underneath the pad and run an Ethernet cable up to the control boxes on the first stage, like we did the first time around.”

The hot-fire of the two engines would last about half a minute and put the new engines through their paces.

“Right now we’re thinking about 32 seconds of firing, we’ll hit all three power levels that we plan to use in flight (and) we’ll steer the nozzles during the test.

In parallel with the work to be conducted with the hot-fire test on the pad, the hardware that will fly the OA-5 will be processed for its launch. However, the tested first stage won’t be the rocket to loft that Cygnus.

“The OA-5 flight is going to use a different set of hardware and we just received those cores – the stage one core, which is the tank set and the airframe. We received two of those on a ship from Ukraine – (KB) Yuzhnoye and Yuzhmash build those for us. So now we have three cores at Wallops and that second core is going to be used for OA-5,” Eberly added.

“We started the receiving and inspection process on that and so we’ll have a parallel operation where we’ll be building up the stage test article in parallel with processing for OA-5.”

The engines for OA-5 arrived on an airplane to Dulles from Energomash and transported by truck down to Wallops.

Along with the thrust frame and the feedlines, all the major elements of the first stage for OA-5 were expected to be together by the time of this article’s publication.

After the hot-fire, the first stage used for the test will be recycled for the second Antares 200 launch on the OA-7 CRS mission, currently scheduled for launch in October.

The Enhanced Cygnus spacecraft for the OA-5 flight will also be processed to be ready to support a May target date.

“We go to do our pre-ship inspections of that PCM, so that PCM is just getting completed with its final mods,” Hastman explained.

“We (scheduled) a pre-ship review over in Italy in December and that’ll ship out probably mid to late January to go to Wallops.

“We’re shooting to preserve an early May opportunity; NASA is kind of thinking towards the end of May, but we want to try to preserve that early May opportunity. We’ll get that PCM in there (Wallops) in the March timeframe.

“The service module, we typically try to get there about forty days prior to the launch time. That particular service module is pretty much ready to go, so it’s just a matter of when we pull it out of storage, check it out, and ship it to the launch site.”